Substitute for rubber or gutta-percha.



UNITED STATES PATENT FIT-ICE.

ADAM CAIRNS, OF GLASGOW, SCOTLAND.

SUBSTITUTE FOR RUBBER OR GUTTA-PERCHA.

SPECIFICATION forming part of Letters Patent No. 680,426, dated August13, 1901.-

Application filed December 11, 1899.

To aZZ whom it may concern.-

Be it known that I, ADAM CAIRNS, rubberworks manager, a subject of theQueen of the United Kingdom of Great Britain and Ireland, residing at110 Commerce street, Glasgow, Scotland,- have invented new and usefulImprovements in Substitutes for Rubber or Gutta-Percha, of which thefollowing is a specification.

This invention relates to and has for its object the preparation andapplication of an improved substitute for rubber and guttapercha wherebya cheaper and superior result is obtained than is possible with theordinary rubber or gutta-percha substitutes at present employed.

In the carrying out of my invention I take vegetable fiber, preferablyin the form of cot ton, and act on the same with an alkali and bisulfidof carbon in the presence of water; but I sometimes find it convenientto add also a suitable proportion of shale spirit or coaltar, naphtha,and lime. This specially-prepared substitute is then added to anordinary rubber or gutter percha mixing for the production of rubber orgutta -percha goods. With regard to the rubber mixing, in order toneutralize or prevent the injurious action of the alkali on the rubberand to allow of the sulfur exerting its vulcaniz'ing effectI find itconvenient to add a suitable proportion of sulfate of zinc or othersuitable salt. An acid can also be used, but is less convenient in itsapplication.

The ingredients, for instance, in the case of a rubber mixing forwaterproofing cloth, usually consist of rubber,- ordinary substitute,and compounds, which are thoroughly mixed and then made into a doughwith solvent naphtha, and it is when in the doughing-mill that therequisite quantity of the above-described substitute is added andincorporated thoroughly with it. The finished 'ing, covering wire,

$erial No. 739,920. (No specimens-l ordinary way, either wholly orpartly, as the case may require, or the dough may be made thin and runon the fabric with the subsequent application of one or more coats ofthe substitute mixed with rubber and other in-' gredients, or theproofing may, if desired, be finished with one or more coats of purerubber dough.

I find that by the use of rubber mixtures I containing the improvedsubstitute a sheet of rubber is obtained which is less porous andconsiderably cheaper than can otherwise be produced, and in the proofingof cloth a lesser weight is required to make the cloth Water proof thanwould suffice with the ordinary mixings now in use.

In dealing with gutta-percha it is made into a dough with any suitablesolvent and mixed in any suitable proportion with the improvedsubstitute, prepared as hereinbe fore described. I find the saidgutta-percha substitute to be very suitable for use in the manufactureof golf-balls, gutta-percha beltand general electrical purposes.

I claim 1. The herein desc'ribed composition of matter consisting ofvegetable fiber, subjected'to the action of caustic alkali and carbonbisulfid in the presence of water, and rubber or gutta-percha mixings,substantially as de scribed.

2. The herein described composition of matter consisting of vegetablefiber, subjected to the action of caustic alkali and carbon bisulfid inthe presence of water, and mixed with rubber or gutta-percha mixingswith the addition of sulfate of zinc or other suitable salt,substantially as described.-

ADAM CAIRNS.

Witnesses JAMES YATE JOHNSON, JAMES LAWRENCE WELLS.

